In water, these molecules spontaneously align â with their heads facing outward and their tails lining up in the bilayer's interior. Thus, the hydrophilic heads of the glycerophospholipids in a cell's plasma membrane face both the water-based cytoplasm and the exterior of the cell.
An MRI (magnetic resonance imaging) scan is an imaging test that uses powerful magnets and radio waves to create pictures of the body. It does not use radiation (x-rays). Single MRI images are called slices. The images can be stored on a computer or printed on film.
Magnetic Resonance Imaging (MRI) of the Spine. An MRI is a test that uses a magnetic field and pulses of radio wave energy to make pictures of the spine. In many cases, an MRI gives different information than an X-ray, an ultrasound, or a CT scan. An MRI also may show problems that cannot be seen with other imaging tests.